Leaders of the military coup in the tiny west African nation of Sao Tome and Principe say they are dissolving all state bodies and setting up a military government. The coup comes as the island state is about to reap its first revenues from offshore oil fields.

In a statement read by a journalist on state media Wednesday, renegade soldiers said they carried out their coup in the pre-dawn hours to reverse the country's economic and social decline.

The statement also ordered all members of the parliament and the government to report to police stations. The renegades appealed to the international community not to intervene, even as diplomats in the capital, Sao Tome, tried to act as mediators.

The former colonial power, Portugal and neighboring Nigeria immediately condemned the coup and called for the return of constitutional order. Nigeria also warned the coup leaders against endangering the lives of Nigerian citizens.

The soldiers have already detained all top members of the government, except the foreign affairs minister, who is in Portugal, and President Fradique de Menezes, who is on a private visit to Nigeria. Portuguese officials have called on all residents in Sao Tome to remain inside their homes until the situation is clarified.

Machine-gun wielding mutineers have also taken control of government buildings, state media, the central bank and the airport. No injuries were reported.

The former Portuguese colony, which is made up of small islands, has a population of about 150,000 people, and depends mostly on fishing and international aid.

But political instability has increased in recent years since discoveries showed the country may have vast oil reserves.

The auctioning of drilling permits for several Gulf of Guinea oil blocks jointly owned with Nigeria was expected to net an initial $100 million for the islands by next year.

Some studies suggest Sao Tome and Principe, which is one of the world's poorest countries, could have up to four billion barrels of crude oil in its territorial waters.

The de Menezes government had recently invited the U.S. military to establish a naval base on the islands to protect growing American oil interests in West Africa.